Divergent Synthesis of [3,4]-Fused 3-Alkenyl-Oxindoles via Propargyl Alcohol-Triggered C(sp³)–H Functionalization

ACS Catalysis, Год журнала: 2021, Номер 12(2), С. 943 - 952

Опубликована: Дек. 30, 2021

[3,4]-Fused oxindoles are the core structures of naturally occurring oxindole alkaloids, and fused tricyclic have distinguished themselves with unique biological activities. Herein, we developed a synthetic strategy for divergent synthesis diverse types [3,4]-seven- or six-membered ring-fused 3-alkenyl-oxindoles incorporating benzazepine significant building blocks from propargyl alcohols via cascade nucleophilic substitution/site-selective hydride transfer/cyclization process unprecedentedly. In addition, variety nucleophiles, including H2O, were available controllable construction wide range conjugated alkenes, ketones, allyl encompassing natural products pharmaceutical motifs utilization 4-amine substituted isatins widespread terminal alkyne-derived alcohols. Furthermore, utility methodology mechanistic studies also well presented.

Язык: Английский

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Divergent synthesis of nitrogen heterocyclesviaH₂O-mediated hydride transfer reactions

Green Chemistry, Год журнала: 2023, Номер 25(13), С. 5134 - 5141

Опубликована: Янв. 1, 2023

The H 2 O-promoted controllable synthesis of diverse 3-carboxyl and 3-acyl substituted tetrahydroquinolines 3,4-dihydroquinolin-2(1 )-ones from readily available feedstocks was developed by a hydride transfer strategy.

Язык: Английский

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Unmasking the reverse reactivity of cyclic N-sulfonyl ketimines: multifaceted applications in organic synthesis

Chemical Communications, Год журнала: 2021, Номер 57(72), С. 9010 - 9028

Опубликована: Янв. 1, 2021

This feature article covers the recent status on reactivities of α-alkyl cyclic N -sulfonyl ketimines as resourceful nucleophiles, targeting fused carbo- and heterocycles, aza-arenes etc . In addition, mechanistic studies have been presented.

Язык: Английский

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Redox-triggered dearomative [5 + 1] annulation of indoles with O-alkyl ortho-oxybenzaldehydes for the synthesis of spirochromanes

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(6), С. 1668 - 1674

Опубликована: Янв. 1, 2022

The dearomative [5 + 1] annulation of 2-methylindoles with new five-membered synthon was developed through cascade [1,5]-hydride transfer/dearomative cyclization in HFIP for the synthesis spirochromanes bearing 2-methylindolenine skeleton.

Язык: Английский

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Redox-Triggered Switchable Synthesis of 3,4-Dihydroquinolin-2(1H)-one Derivatives via Hydride Transfer/N-Dealkylation/N-Acylation

Organic Letters, Год журнала: 2020, Номер 23(2), С. 358 - 364

Опубликована: Дек. 23, 2020

The switchable synthesis of 3-non, 3-mono, 3,3′-disubstituted 3,4-dihydroquinolin-2(1H)-ones was developed through a redox-neutral hydride-transfer/N-dealkylation/N-acylation strategy from o-aminobenzaldehyde with 4-hydroxycoumarin, and Meldrum's acid, respectively. unprecedented for the 3,3′-highly functionalized 3,4-dihydroquinolin-2(1H)-one has been realized in situ utilization released HCHO via o-QM involved Michael addition. In addition, synthetic utility this protocol well illustrated concise CYP11B2 inhibitor.

Язык: Английский

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Borane-catalyzed cascade Friedel–Crafts alkylation/[1,5]-hydride transfer/Mannich cyclization to afford tetrahydroquinolines

Chemical Science, Год журнала: 2021, Номер 13(3), С. 775 - 780

Опубликована: Дек. 20, 2021

An unprecedented redox-neutral annulation reaction of tertiary anilines with electron-deficient alkynes was developed that proceeds through a cascade Friedel-Crafts alkylation/[1,5]-hydride transfer/Mannich cyclization sequence. Under B(C6F5)3 catalysis, range functionalized 1,2,3,4-tetrahydroquinolines were facilely constructed in moderate to good yields exclusive 3,4-anti-stereochemistry. The commercial availability the catalyst and high atom step economy procedure, together metal-free external oxidant-free conditions, make this an attractive method organic synthesis.

Язык: Английский

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HFIP-mediated three-component imidization of electron-rich arenes with in situ formed spiroindolenines for facile construction of 2-arylspiroindolenines

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(6), С. 1696 - 1702

Опубликована: Янв. 1, 2022

The three-component reaction of o -aminobenzaldehydes with 5-hydroxyindole and electron-rich arenes has been achieved through HFIP-mediated cascade hydride transfer/dearomative cyclization/CDC-type imidization at room temperature under air.

Язык: Английский

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The Cascade [1,5]-Hydride Shift/Intramolecular C(sp3)–H Activation: A Powerful Approach to the Construction of Spiro-Tetrahydroquinoline Skeleton

Frontiers in Chemistry, Год журнала: 2022, Номер 10

Опубликована: Апрель 7, 2022

The direct functionalization of inert C–H bonds is regarded as one the most powerful strategies to form various chemical and construct complex structures. Although significant advancements have been witnessed in area transition metal-catalyzed bonds, several challenges, such utilization removal expensive metal complexes, limited substrate scope large-scale capacity, poor atom economy removing guiding groups coordinated metal, cannot fully fulfill high standard modern green chemistry nowadays. Over past decades, due its inherent advantage compared with a strategy, hydride shift activation that applies “ tert -amino effect” into common omnipresent C(sp 3 )–H adjacent -amines has attracted much attention from chemists. In particular, intramolecular [1,5]-hydride activation, mode, enables rapid effective production multifunctionally frameworks, especially spiro-tetrahydroquinoline derivatives, which are widely found biologically active natural products pharmaceuticals. great accomplishments achieved this promising field, rarely an updated review systematically summarized these important progresses despite scattered reports documented reviews. Hence, review, we will summarize advances cascade shift/intramolecular )-H perspective build skeleton, content categorized by structure type final containing pharmaceutical units. Besides, current limitations well future directions field also pointed out. We hope our could provide quick look offer some inspiration for research on strategy future.

Язык: Английский

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Aromatization-driven cascade [1,5]-hydride transfer/cyclization for synthesis of spirochromanes

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(7), С. 1796 - 1802

Опубликована: Янв. 1, 2023

An aromatization-driven hydride transfer-involved α-C(sp 3 )–H bond functionalization of the oxygen atom was developed. Easily prepared p -quinone methides were applied to initiate [1,5]-hydride transfer/cyclization for generating spirochromanes.

Язык: Английский

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Substrate-Controlled Domino Reaction ofN-Sulfonyl Ketimines with 2-Aroyl-1-chlorocyclopropanecarboxylates: Access to Cyclopenta[c]chromenes and Benzo[f]cyclopenta[d][1,2]thiazepine Dioxides

The Journal of Organic Chemistry, Год журнала: 2021, Номер 86(9), С. 6721 - 6733

Опубликована: Апрель 12, 2021

An unprecedented substrate-controlled annulation method for the synthesis of fascinating classes angularly fused cyclopenta[c]chromenes and benzo[f]cyclopenta[d][1,2]thiazepine 5,5-dioxide derivatives in good to high chemical yields is reported. This Michael-initiated ring-expansion reaction would enable two C–C one C–O or C–N bonds by a judicious choice carbonucleophiles, either 4-alkyl 3-alkyl-substituted N-sulfonyl ketimines, respectively, with series donor–acceptor cyclopropane scaffolds as 4C sources promoted DBU. Moreover, this eco-friendly mild enough protect different kinds functionalities. Importantly, prepared fulvene were smoothly transformed into special class hexahydrocyclopenta[c]chromenes single cis–cis–cis–cis diastereomers excellent simple catalytic hydrogenation reaction.

Язык: Английский

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